Moderators of long-term treatment outcome when comparing two group interventions for adolescents with ADHD: who benefits more from DBT-based skills training?

Background: Psychosocial interventions for adolescents with attention-deficit/hyperactivity disorder (ADHD), targeting emotional dysregulation and impulsive behaviors, have been requested, but the heterogeneity within this group makes it unlikely that there is one treatment that fits all. The aim of this study was to identify which adolescents with ADHD might have an effect from a structured skills training group (SSTG) based on dialectical behavioral therapy, by exploring pre-treatment characteristics as potential moderators of long-term treatment outcome. Methods: This study was based on follow-up data from a randomized controlled trial comparing the SSTG (n = 71) to a psychoeducational control intervention (n = 57) for adolescents with ADHD (15-18 years old). Clinical characteristics (sex, age, medication status, ADHD presentation, severity of ADHD symptom, psychiatric comorbidity, impairment of emotional dysregulation and functional impairment) were explored as potential moderators of pre-treatment to follow-up change in ADHD symptoms and functional impairment. Moderation analyses were performed using the PROCESS macro for SPSS. Results: Three moderators (severity of hyperactivity/impulsivity, conduct problems and impairment of emotional dysregulation) were identified in regard to the outcome self-rated change in ADHD symptoms. Participants with elevated pre-scores on these variables had a better effect of the SSTG than of the psychoeducational control intervention. No moderators were found in regard to the parental-rated outcomes. Conclusions: The SSTG seems to be beneficial for adolescents with ADHD who perceive pronounced symptoms of hyperactivity/impulsivity, conduct problems and emotional dysregulation. Our findings need to be confirmed in future trials evaluating dialectical behavioral therapy-based skills training for adolescents with ADHD, where these moderators could be used as criteria for inclusion or stratification.